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<p>Composite materials have been invented and used to make all kinds of industrial products, such as automobiles, aircraft, sports equipment etc., for many years. Excellent properties such as high specific stiffness and strength have been recognized and studied for decades, motivating the use of composite materials. However, the design of composite structures still remains a challenge. Existing design tools are not adequate to exploit the full benefits of composites. Many tools are still based on the traditional material selection paradigm created for isotropic homogeneous materials, separated from the shape design. This will lose the coupling effects between composite materials and the geometry and lead to less optimum design of the structure. Hence, due to heterogeneity and anisotropy inherent in composites, it is necessary to model composite parts with appropriate microstructures  instead of simplistically replacing composites as black aluminum and consider materials and geometry at the same time.</p> <p><br></p> <p>This work mainly focuses on the design problems of complex material-structural systems through computational analyses. Complex material-structural systems are structures made of materials that have microstructures smaller than the overall structural dimension but still obeying the continuum assumption, such as fiber reinforced laminates, sandwich structures, and meta-materials, to name a few. This work aims to propose a new design-by-analysis framework based on the mechanics of structure genome (MSG), because of its capability in accurate and efficient predictions of effective properties  for different solid/structural models and three-dimensional local fields (stresses, strains, failure status, etc). The main task is to implement the proposed framework by developing new tools and integrating these tools into a complete design toolkit. The main contribution of this work is a new efficient high-fidelity design-by-analysis framework for complex material-structural systems.</p> <p><br></p> <p>The proposed design framework contains the following components. 1) MSG and its companion code SwiftComp is the theoretical foundation for structural analysis in this design framework. This is used to model the complex details of the composite structures. This approach provides engineers the flexibility to use different multiscale modeling strategies. 2) Structure Gene (SG) builder creates finite element-based model inputs for SwiftComp using design parameters defining the structure. This helps designers deal with realistic and meaningful engineering parameters directly without expert knowledge of finite element analysis. 3) Interface is developed using Python for easy access to needed data such as structural properties and failure status. This is used as the integrator linking all components and/or other tools outside this framework. 4) Design optimization methods and iteration controller are used for conducting the actual design studies such as parametric study, optimization, surrogate modeling, and uncertainty quantification. This is achieved by integrating Dakota into this framework. 5) Structural analysis tool is used for  computing global structural responses. This is used if an integrated MSG-based global analysis process is needed.</p> <p><br></p> <p>Several realistic design problems of composite structures are used to demonstrate the capabilities of the proposed framework. Parameter study of a simple fiber reinforce laminated structure is carried out for investigating the following: comparing with traditional design-by-analysis approaches, whether the new approach can bring new understandings on parameter-response relations and because of new parameterization methods and more accurate analysis results. A realistic helicopter rotor blade is used to demonstrate the optimization capability of this framework. The geometry and material of composite rotor blades are optimized to reach desired structural performance. The rotor blade is also used to show the capability of strength-based design using surrogate models of sectional failure criteria. A thin-walled composite shell structure is used to demonstrate the capability of designing variable stiffness structures by steering in-plane orientations of fibers of the laminate. Finally, the tool is used to study and design auxetic laminated composite materials which have negative Poisson's ratios.</p>

This project deals with the improvement of a wire boom deployment system to be used on a proposed Rocket Experiments for University Students (REXUS) mission. The system to be improved was previously used on the Small Payload for Investigation of Disturbances in Electrojet by Rockets (SPIDER-2) mission and the objective was to make that system more robust and reliable as well as easier to assemble. The wire boom system itself consisted of four probes for measuring electric fields as well as four probes to measure space plasma properties. These all needed to be deployed from a free flying unit, while still being attached to it with thin wires. The wires were stored on spools which unwound using a piezoelectric motor and the probes were deployed by releasing a locking mechanism and then pushing them out with springs. Based on that, along with deployment testing of the SPIDER-2 system, the areas to improve were selected. It was chosen to focus on getting the probes out of the hull more reliably and making the spools rotate more evenly while being more constrained. In addition, focus was placed on simplifying assembly and bettering the guiding of the wires wherever possible. To accomplish this, in the end, nearly every part was replaced or altered. This resulted in the system being able to deploy even without any rotation to provide centrifugal force and also made the wire guiding better to decrease the chance of tangling. However, more work remains to be done on the system to finalize the new parts and to make further improvements on parts that were not handled during this project. / Detta projekt hanterar förbättring av ett system för att fälla ut trådbommar från en fritt fallande enhet. Arbetet blir en fortsättning på det som tidigare gjorts för uppdrag kallade SPIDER och SPIDER-2 men är denna gång främst riktad mot ett studentexperiment. De huvudsakliga syftena med arbetet var att förbättre tillförlitligheten och robustheten samt att förenkla ihopsättningen av systemet. Dessa kom från de tidigare uppdragen systemet använts för. System består av fyra prober som mäter elektriska fält samt fyra som mäter egenskaper av plasman kring jorden. Dessa prober måste placeras en bit bort från den fritt fallande enheten för att göra mätningar. De kopplas till enheten med tunna trådar som lagras på spolar innan proberna ska fällas ut. En piezoelektrisk motor roterar sedan spolarna samtidigt som proberna puttas ut ur enheten under utfällning. Egen testning samt tidigare erfarenhet kombinerades sedan för att bestämma att arbetet skulle fokusera på att få ut proberna mer tillförlitligt samt göra spolarnas rotation mer jämn och kontrollerad. Samtidigt skulle även ihopsättningen förenklas där det gick och åtgärder för att minska chans för trassel tas där det gick. Resultatet blev att i stort sett alla delar av systemet byttes ut och det visade sig efter tester att fungera precis som tänkt. Proberna kunde därför lämna enheten utan någon rotation och trådarna kontrollerades bättre, för att minimera risken för trassel. Däremot finns det mer arbete att göra innan systemet är redo för att användas. Detta inkluderar både att färdigställa de delar som hanterats i detta arbete samt att jobba med de delar som inte hanns med.

Cette thèse, qui étudie les effets des mutations économiques sur les parcours de vie des générations, s'inscrit au coeur de l'actuel débat théorique qui oppose deux grandes thèses relatives au changement culturel : celle de la montée des valeurs postmatérialistes et celle du retour des valeurs matérialistes. Du point de vue empirique, l'auteur examine les effets des mutations économiques sur les parcours de vie de deux cohortes de baby-boomers québécois (1942-51 et 1962-71), examen qui porte plus particulièrement sur le parcours professionnel, les modalités d'entrée dans l'âge adulte, les modes d'agencement travail-famille et l'éthique du travail. L'étude montre qu'en dépit de parcours professionnels et familiaux passablement différents, les cohortes présentent d'importantes similitudes, ce qui remet en question la solidité tant des thèses fondées sur l'existence d'un conflit intergénérationnel que de celles qui soutiennent· le retour des valeurs matérialistes. En effet, il appert que les mutations économiques des dernières décennies n'ont pas modifié de manière substantielle le mouvement de fond amorcé depuis la fin de la Seconde Guerre mondiale, à savoir la montée de valeurs liées à la réalisation de soi. Si notre étude valide en partie la thèsepostmatérialiste du changement, elle n'en nuance pas moins certains aspects. Par exemple, tout indique que le changement culturel ne s'effectue pas simplement par le remplacement des générations, mais aussi par l'évolution des valeurs au sein des différentes générations au cours d'une même période historique. Par ailleurs, cette étude illustre aussi le fait que le concept de cohorte, bien qu'utile pour étudier le changement, tend à masquer les différences au sein d'une même cohorte, ce qui conduit souvent à de trop grandes généralisations.

by Chan Chui-mi, Rebecca and Pong Hei-ming, David. / Thesis (M.B.A.)--Chinese University of Hong Kong, 1990. / Bibliography: leaf 138. / TABLES OF CONTENTS --- p.ii / LIST OF ILLUSTRATIONS --- p.v / LIST OF TABLES --- p.vi / ACKNOWLEDGMENTS --- p.vii / Chapter I. --- BACKGROUND AND PROBLEM STATEMENT --- p.1 / Background on the Yuppie Phenomenon --- p.1 / Baby-boomers and Yuppies --- p.1 / Yuppies in the U.S.A. --- p.1 / The Yuppie Phenomenon in Hong Kong --- p.3 / Statement of the Problem --- p.5 / Chapter II. --- LITERATURE REVIEW --- p.6 / Yuppies : Origin and Definition --- p.8 / Yuppies : Their Inner World --- p.10 / Yuppies : An International Flavor --- p.13 / Yuppies in Hong Kong --- p.15 / Returnees --- p.16 / Working Educated Women --- p.16 / Yuppies : Life-style and Marketing Imp1ications --- p.17 / Yuppies : Fading Away --- p.17 / Conclusions --- p.22 / Chapter III. --- RESEARCH METHODOLOGY --- p.23 / Hypotheses Development --- p.23 / Psychological Traits --- p.24 / Status Conscious --- p.24 / Quality Conscious --- p.24 / Motivation and Drive --- p.25 / Innovative and Adventurous --- p.25 / Health-conscious --- p.25 / Time-conscious --- p.26 / Concern for Children --- p.26 / Media Selection --- p.26 / Market/Consumption Behavior --- p.27 / Demographic Profile --- p.28 / Target Group Definition --- p.29 / Age --- p.30 / Personal Income --- p.30 / Education --- p.31 / Data Collection --- p.31 / Sampling Frame --- p.31 / Questionnaire Design --- p.32 / Psychological Traits --- p.32 / Market Behavior --- p.33 / Demographic Profile --- p.35 / Data Analysis --- p.35 / Summary --- p.36 / Chapter IV. --- DATA COLLECTION AND ANALYSIS --- p.37 / Pilot Test --- p.37 / Data Collection in Practice --- p.38 / Sample Group --- p.38 / Post-coding of Part I Answers --- p.39 / Post-coding of Part II Answers --- p.39 / Descriptive Statistics --- p.46 / Frequency Statistics --- p.46 / Hypothesis Testing of Psychological --- p.46 / Traits By Two-Sample T-test / Analysis of Yuppies， Consumption By One-Sample Chi-Square --- p.48 / Cross Tabulation and Chi-Square --- p.51 / Statistic on Consumption of Yuppies / Vis-a-vis the Control Group / Demographic Characteristics of Yuppies --- p.54 / Cluster Analysis --- p.56 / Primary Cluster Analysis --- p.56 / Secondary Cluster Analysis --- p.58 / Demographic Characteristics Redefined --- p.62 / Chapter V. --- MARKETING IMPLICATIONS --- p.63 / Executive Summary --- p.63 / Marketing Implications --- p.64 / Marketing of Social Goods --- p.65 / Marketing of Non-social Goods --- p.66 / New Market Segments --- p.67 / New Product Attributes --- p.67 / New Distribution Channels --- p.68 / New Promotion Messages --- p.68 / Differentiated Pricing Strategies --- p.69 / Recommendations for Future Studies --- p.77 / APPENDIX --- p.71 / Chapter 1 --- Initial Questionnaire for Pilot Test --- p.71 / Chapter 2 --- Pilot Test and Spearman Coefficient for Internal Consistency Test --- p.89 / Chapter 3.1 --- Revised Questionnaire in English --- p.91 / Chapter 3.2 --- Revised Questionnaire in Chinese --- p.102 / Chapter 4 --- "Descriptive Statistics on Mean, Standard Deviation, Maximum and Minimum Values of Records" --- p.113 / Chapter 5 --- Hypothesis Testing of Psychological Traits by Two-sample T-test --- p.114 / Chapter 6 --- T-test Results on the Mean Difference for Each Group of Attitude Statements between the Yuppies and the Control Group --- p.116 / Chapter 7 --- One Sample Chi-square Test --- p.120 / Chapter 8 --- Results of One Sample Chi-square on Yuppies， Consumption --- p.121 / Chapter 9 --- Cross Tabulation of Chi-square Statistics on Consumption of Yuppies vis-a-vis the Control Group --- p.127 / Chapter 10 --- Frequency Statistics on Yuppie Demographics --- p.130 / Chapter 11 --- Cluster Analysis --- p.135 / BIBLIOGRAPHY --- p.136

Cette thèse propose d’expliquer le faible taux d’emploi enregistré en France après 55 ans par les risques de fragilité économique, professionnelle, sociale et familiale que révèle le passage à la retraite. Elle repose sur le postulat de la liberté de choix dans la décision de retraite.En 2005, une étude quantitative sur les intentions de départ à la retraite a été menée auprès de 1004 individus en emploi, âgés de 54 à 59 ans. Les trajectoires personnelles comportant leur part d’incertitude et de changements, 31 entretiens semi-directifs ont été réalisés auprès de membres de l’échantillon initial, cinq ans plus tard, afin de permettre un suivi longitudinal. L’articulation des représentations de la retraite, du parcours professionnel et de la trajectoire familiale vise à cerner les écarts entre les projets et les choix adoptés et à déterminer les facteurs-clés impliqués dans la décision.Cette thèse souligne tout d’abord que la majorité des projets initiaux ne sont pas concrétisés. Le déterminisme du contexte professionnel sur la décision de retraite explique en partie ces réajustements : dégradation des conditions de travail, déclassement en fin de carrière, stigmatisation sont autant d’arguments susceptibles d’inciter les individus à partir à la retraite plus tôt que prévu. Mais les itinéraires familiaux pèsent également sur ces choix : « pivots générationnels » entre des parents âgés et des descendants à soutenir, les jeunes retraités doivent faire face à des charges familiales qui influent sur leur décision. Enfin, cette recherche met en évidence la manière dont les jeunes retraités issus du baby-boom, très attachés à leur liberté individuelle tout au long de leur parcours, défendent la préservation d’espaces personnels (individualisation des pratiques), adoptant ainsi des modèles familiaux et une manière de vivre la retraite inédits. / This thesis seeks to explain the low employment rate in France for people aged 55 years and above in terms of the increasing risk of economic, professional, social and family fragility observed in the transition to retirement. The research is based on the postulate of “free choice” in retirement decisions.In 2005, a quantitative study on the intentions of retirement was conducted among 1,004 employed individuals aged 54-59 years. As personal life courses are marked by change and uncertainties, a longitudinal analysis comprising 31 semi-structured interviews was conducted five years later with participants of the initial sample. The combined study of representations of retirement, end of career and family context allows differences to be identified between plans and the final adopted choices, and the key factors involved in the final decision to be determined.First of all, this thesis demonstrates that most of the initial plans are not realised. The determinism of the professional context on the retirement decision partly explains the observed adjustments: a degradation of working conditions, the assignation of under-qualified tasks at the end of a career, and stigmatisation are all factors that encourage people to retire earlier than expected. But the family environment also influences choices: as "generational pivots" between elderly parents and children to support, young retired people have to face family responsibilities that affect their decisions. Finally, this research highlights how young retirees from the baby boom, for whom individual freedom played a central role in their past life course, adopt new family models and a new way of living (the preservation of “individual spaces” and individualised behaviours) during retirement.

Main subject of this diploma thesis is real estate sector, his basic principles, structure and factors of influence. Diploma thesis is analysing actual post - crisis trends in real estate sector, origins and causes of these trends. Special attention is concentrated into the specific development and surroundings of real estate sector in Czech republic. The analysis of the sector transformation intensity is used for searching of future potential of real estate sector, future trends and appropriate measures for healthy growth of real estate sector and long - term sustainability of real estate sector projects. The next one of the main baselines of the thesis is research of behavioral changes of real estate market demand because of cyclicality of real estate market. The research shows context between real estate cycle and business cycle and analyses typical behavioral reaction of demand in various phases of real estate sector cycle.

Questa tesi esamina l’interazione tra aspettative eterogenee e il rapporto creditore-debitore. In letteratura, non è ancora chiara la natura dell’interazione tra cicli del credito e aspettative individuali. Per questo motivo ho capito che sarebbe stato importante iniziare dai lavori seminali in entrambi i campi, ovvero Kiyotaki & Moore (1997) e Brock & Hommes (1997). Il mio principale obbiettivo è stato quello di studiare più nel dettaglio il funzionamento del vincolo di garanzia. Il fil rouge dell’intera tesi, infatti, è l’analisi del ruolo delle frizioni finanziarie nell’andamento del prezzo di un asset collateralizzato. In particolare, presento un modello dove l’ipotesi di aspettative razionali viene abbandonata. I risultati del primo capitolo rivelano che le aspettative individuali sono una fonte importante di instabilità, anche se la configurazione iniziale risulta stabile. L’elemento che provoca questa instabilità è la bancarotta causata dalla divergenza tra le aspettative di creditori e debitori sul prezzo dell’asset collateralizzato. Poi, nel secondo capitolo, effettuo un esperimento di learning-to-forecast. Fondato sul modello del primo capitolo, ha come obbiettivo quello di testare se e come la volatilità è legata alle percezioni di rischio dei creditori. Ciò che emerge è che ridurre il credito in risposta ad un aumento delle insolvenze in realtà conduce a scenari addirittura peggiori dove il benessere totale si deteriora e il numero delle bancarotte aumenta. / This thesis examines the interaction between heterogeneous expectations and the borrower-lender relationship. In the literature, the nature of the interaction between credit cycle and individual expectations is still unclear. Therefore I realized it was important to start from the seminal works in both fields, that is Kiyotaki & Moore (1997) and Brock & Hommes (1997). My main concern has been to gain insights into the collateral constraint. The common thread of the whole thesis, indeed, is to analyse the role of financial frictions in the price development of a collateralized asset. In particular, I introduce a model where rational expectations are dropped. The results of the first chapter reveal that even in a simple and stable setting, individual beliefs are an important source of instability. The driver of this instability is the bankruptcy caused by the divergence between borrowers' and lenders' price expectations on a collateralized asset. Then, I conduct an online learning-to-forecast experiment. Founded on the model of the first chapter, it tests whether and how volatility is related to lender-level risk perceptions. What emerges is that to shrink credit in response to an increase in defaults actually leads to worse scenarios where total welfare deteriorates and the number of bankruptcies increases.

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